I have an 85 Baja 190 Sunsport with a 5.0L Mercruiser engine that I am rebuilding. The engine currently uses a Thunderbolt IV ignition system. While rebuilding the engine I am planning on installing a larger duration and lift cam, different intake manifold, and a 4 barrel carburetor. My question is with the installation of the performance parts, is the existing ignition system capable of maintaining the proper amount of advance thru out the rpm range? Or does the advance curve within the ignition module need to be change and if so how do I change it?